Spinning top precess only when its axis is inclined

AI Thread Summary
A spinning top precesses only when its axis is inclined to the vertical due to the torque exerted by gravity. When the top is tilted, gravity creates a torque at the support point that acts perpendicular to the angular momentum, resulting in precession. In contrast, a perfectly vertical spinning top experiences no torque, leading to the absence of precession. This relationship highlights the importance of angular momentum and gravitational forces in the dynamics of spinning objects. Understanding this phenomenon is crucial for applications in physics and engineering.
Amith2006
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Sir,
Why does a spinning top precess only when its axis is inclined to the vertical direction of the gravitational field?
 
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When the top spins at an angle to the vertical, gravity exerts a torque (via the reaction force at the support point) perpendicular to the top's angular momentum, which creates the precession. If the spinning top is perfectly vertical, there is no such torque and thus no precession.
 

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